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Question
NARRBEGIN: SA_88_91The manager of a consulting firm in Lansing, Michigan, is trying to assess the effectiveness of computer skills training given to all new entry-level professionals. In an effort to make such an assessment, he administers a computer skills test immediately before and after the training program to each of 20 randomly chosen employees. The pre-training and post-training scores of these 20 individuals are shown in the table below.
| Employee | Score before | Score after |
| 1 | 62 | 77 |
| 2 | 63 | 77 |
| 3 | 74 | 83 |
| 4 | 64 | 88 |
| 5 | 84 | 80 |
| 6 | 81 | 80 |
| 7 | 54 | 83 |
| 8 | 61 | 88 |
| 9 | 81 | 80 |
| 10 | 86 | 88 |
| 11 | 75 | 93 |
| 12 | 71 | 78 |
| 13 | 86 | 82 |
| 14 | 74 | 84 |
| 15 | 65 | 86 |
| 16 | 90 | 89 |
| 17 | 72 | 81 |
| 18 | 71 | 90 |
| 19 | 85 | 86 |
| 20 | 66 | 92 |
(A) Is this two-sample data or paired data. Explain your answer.
(B) Specify an appropriate hypothesis test.
(C) Using a 10% level of significance, do the given sample data support that the firm's training programs is effective in increasing the new employee's computer skills?
(D) Using a 1% level of significance, do the given sample data support that the firm's training programs is effective in increasing the new employee's working knowledge of computing ?
Answer
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